The average age of menopause in the United States is around 51 years old, but the onset can widely vary. Premature menopause refers to menopause of onset at or before 40 years of age. This can occur because of  a variety of causes, including surgery (i.e. bilateral oophorectomy, removal of ovaries), chemotherapy or pelvic radiation treatments for cancer, chromosomal or genetic defects, and spontaneous premature ovarian failure.

For women undergoing premature menopause, symptoms can be similar to those of regular menopause. Symptoms include  hot flashes, night sweats, vaginal dryness, and mood changes. Longitudinally, however, the symptoms may different between those who undergo premature menopause and those who undergo menopause at roughly the average age. New research shows that premature menopause may be associated with long-term negative effects on cognitive function.

A study based on a sample of 4868 women tested cognition at baseline, two, four, and seven years, and it also looked at the effects of the type of menopause, whether natural or surgical, could play a role.

Natural menopause was reported by 79% of the 4868 participants, 10% underwent menopause from surgical causes, and 11% reported menopause from other treatment causes including radiation or chemotherapy. Approximately 7.6% of the women in the study had a premature menopause, and the study further delineated 12.8% of the women had an early menopause (between 41 and 45 years of age).

Results showed that women who underwent premature menopause had a more than 40% increased risk of poor performance on verbal fluency and visual memory tasks, compared to those who experienced menopause at or after the age of 50. Women who underwent premature menopause also were associated with a 35% increased risk of decline in psychomotor speed. There was no significant association with the risk of dementia.

Both premature menopause secondary to surgery and premature ovarian failure, were associated with long-term negative effects on cognitive function, which cannot entirely be answered by hormone therapy. Researchers agree more studying needs to be done to better understand the potential benefits using hormone therapy.

Healthcare professionals should be aware of the potentially significant impact premature menopause can have on cognitive function in later life. Professionals should also consider these effects when aiding younger women in the decision-making process of undergoing oophorectomy. To learn more about how menopause can affect you long-term, visit Northwestern's menopause website here.

Source: J Ryan, J Scali, I Carrière, H Amieva, O Rouaud, C Berr, K Ritchie, M-L Ancelin.Impact of a premature menopause on cognitive function in later life. BJOG: An International Journal of Obstetrics & Gynaecology, 2014; DOI: 10.1111/1471-0528.12828

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